From 3faa303a47e0c3b59a53988e0f76018930c6cb1a Mon Sep 17 00:00:00 2001 From: Christophe GISQUET Date: Sun, 1 Jan 2012 18:33:22 +0100 Subject: rv34: DC-only inverse transform When decoding coefficients, detect whether the block is DC-only, and take advantage of this knowledge to perform DC-only inverse transform. This is achieved by: - first, changing the 108x4 element modulo_three_table into a 108 element table (kind of base4), and accessing each value using mask and shifts. - then, checking low bits for 0 (as they represent the presence of higher frequency coefficients) Also provide x86 SIMD code for the DC-only inverse transform. Signed-off-by: Kostya Shishkov --- libavcodec/rv34.c | 95 +++++++++++++++++++++++++++++++++---------------------- 1 file changed, 58 insertions(+), 37 deletions(-) (limited to 'libavcodec/rv34.c') diff --git a/libavcodec/rv34.c b/libavcodec/rv34.c index ec826fd074..6cfefa0e1b 100644 --- a/libavcodec/rv34.c +++ b/libavcodec/rv34.c @@ -204,7 +204,7 @@ static int rv34_decode_cbp(GetBitContext *gb, RV34VLC *vlc, int table) } for(i = 0; i < 4; i++){ - t = modulo_three_table[code][i]; + t = (modulo_three_table[code] >> (6 - 2*i)) & 3; if(t == 1) cbp |= cbp_masks[get_bits1(gb)] << i; if(t == 2) @@ -238,41 +238,42 @@ static inline void decode_coeff(DCTELEM *dst, int coef, int esc, GetBitContext * */ static inline void decode_subblock(DCTELEM *dst, int code, const int is_block2, GetBitContext *gb, VLC *vlc, int q) { - int coeffs[4]; + int flags = modulo_three_table[code]; - coeffs[0] = modulo_three_table[code][0]; - coeffs[1] = modulo_three_table[code][1]; - coeffs[2] = modulo_three_table[code][2]; - coeffs[3] = modulo_three_table[code][3]; - decode_coeff(dst , coeffs[0], 3, gb, vlc, q); + decode_coeff( dst+0, (flags >> 6) , 3, gb, vlc, q); if(is_block2){ - decode_coeff(dst+8, coeffs[1], 2, gb, vlc, q); - decode_coeff(dst+1, coeffs[2], 2, gb, vlc, q); + decode_coeff(dst+8, (flags >> 4) & 3, 2, gb, vlc, q); + decode_coeff(dst+1, (flags >> 2) & 3, 2, gb, vlc, q); }else{ - decode_coeff(dst+1, coeffs[1], 2, gb, vlc, q); - decode_coeff(dst+8, coeffs[2], 2, gb, vlc, q); + decode_coeff(dst+1, (flags >> 4) & 3, 2, gb, vlc, q); + decode_coeff(dst+8, (flags >> 2) & 3, 2, gb, vlc, q); } - decode_coeff(dst+9, coeffs[3], 2, gb, vlc, q); + decode_coeff( dst+9, (flags >> 0) & 3, 2, gb, vlc, q); +} + +/** + * Decode a single coefficient. + */ +static inline void decode_subblock1(DCTELEM *dst, int code, GetBitContext *gb, VLC *vlc, int q) +{ + int coeff = modulo_three_table[code] >> 6; + decode_coeff(dst, coeff, 3, gb, vlc, q); } static inline void decode_subblock3(DCTELEM *dst, int code, const int is_block2, GetBitContext *gb, VLC *vlc, int q_dc, int q_ac1, int q_ac2) { - int coeffs[4]; + int flags = modulo_three_table[code]; - coeffs[0] = modulo_three_table[code][0]; - coeffs[1] = modulo_three_table[code][1]; - coeffs[2] = modulo_three_table[code][2]; - coeffs[3] = modulo_three_table[code][3]; - decode_coeff(dst , coeffs[0], 3, gb, vlc, q_dc); + decode_coeff( dst+0, (flags >> 6) , 3, gb, vlc, q_dc); if(is_block2){ - decode_coeff(dst+8, coeffs[1], 2, gb, vlc, q_ac1); - decode_coeff(dst+1, coeffs[2], 2, gb, vlc, q_ac1); + decode_coeff(dst+8, (flags >> 4) & 3, 2, gb, vlc, q_ac1); + decode_coeff(dst+1, (flags >> 2) & 3, 2, gb, vlc, q_ac1); }else{ - decode_coeff(dst+1, coeffs[1], 2, gb, vlc, q_ac1); - decode_coeff(dst+8, coeffs[2], 2, gb, vlc, q_ac1); + decode_coeff(dst+1, (flags >> 4) & 3, 2, gb, vlc, q_ac1); + decode_coeff(dst+8, (flags >> 2) & 3, 2, gb, vlc, q_ac1); } - decode_coeff(dst+9, coeffs[3], 2, gb, vlc, q_ac2); + decode_coeff( dst+9, (flags >> 0) & 3, 2, gb, vlc, q_ac2); } /** @@ -286,16 +287,24 @@ static inline void decode_subblock3(DCTELEM *dst, int code, const int is_block2, * o--o */ -static inline void rv34_decode_block(DCTELEM *dst, GetBitContext *gb, RV34VLC *rvlc, int fc, int sc, int q_dc, int q_ac1, int q_ac2) +static inline int rv34_decode_block(DCTELEM *dst, GetBitContext *gb, RV34VLC *rvlc, int fc, int sc, int q_dc, int q_ac1, int q_ac2) { - int code, pattern; + int code, pattern, has_ac = 1; code = get_vlc2(gb, rvlc->first_pattern[fc].table, 9, 2); pattern = code & 0x7; code >>= 3; - decode_subblock3(dst, code, 0, gb, &rvlc->coefficient, q_dc, q_ac1, q_ac2); + + if (modulo_three_table[code] & 0x3F) { + decode_subblock3(dst, code, 0, gb, &rvlc->coefficient, q_dc, q_ac1, q_ac2); + } else { + decode_subblock1(dst, code, gb, &rvlc->coefficient, q_dc); + if (!pattern) + return 0; + has_ac = 0; + } if(pattern & 4){ code = get_vlc2(gb, rvlc->second_pattern[sc].table, 9, 2); @@ -309,7 +318,7 @@ static inline void rv34_decode_block(DCTELEM *dst, GetBitContext *gb, RV34VLC *r code = get_vlc2(gb, rvlc->third_pattern[sc].table, 9, 2); decode_subblock(dst + 8*2+2, code, 0, gb, &rvlc->coefficient, q_ac2); } - + return has_ac || pattern; } /** @@ -1118,7 +1127,7 @@ static int rv34_decode_macroblock(RV34DecContext *r, int8_t *intra_types) MpegEncContext *s = &r->s; GetBitContext *gb = &s->gb; int cbp, cbp2; - int q_dc, q_ac; + int q_dc, q_ac, has_ac; int i, blknum, blkoff; LOCAL_ALIGNED_16(DCTELEM, block16, [64]); int luma_dc_quant; @@ -1157,33 +1166,45 @@ static int rv34_decode_macroblock(RV34DecContext *r, int8_t *intra_types) if(r->is16){ q_dc = rv34_qscale_tab[luma_dc_quant]; q_ac = rv34_qscale_tab[s->qscale]; - memset(block16, 0, 64 * sizeof(*block16)); - rv34_decode_block(block16, gb, r->cur_vlcs, 3, 0, q_dc, q_dc, q_ac); - r->rdsp.rv34_inv_transform_tab[1](block16); + s->dsp.clear_block(block16); + if (rv34_decode_block(block16, gb, r->cur_vlcs, 3, 0, q_dc, q_dc, q_ac)) + r->rdsp.rv34_inv_transform_tab[1](block16); + else + r->rdsp.rv34_inv_transform_dc_tab[1](block16); } q_ac = rv34_qscale_tab[s->qscale]; for(i = 0; i < 16; i++, cbp >>= 1){ + DCTELEM *ptr; if(!r->is16 && !(cbp & 1)) continue; blknum = ((i & 2) >> 1) + ((i & 8) >> 2); blkoff = ((i & 1) << 2) + ((i & 4) << 3); + ptr = s->block[blknum] + blkoff; if(cbp & 1) - rv34_decode_block(s->block[blknum] + blkoff, gb, - r->cur_vlcs, r->luma_vlc, 0, q_ac, q_ac, q_ac); + has_ac = rv34_decode_block(ptr, gb, r->cur_vlcs, r->luma_vlc, 0, q_ac, q_ac, q_ac); + else + has_ac = 0; if(r->is16) //FIXME: optimize - s->block[blknum][blkoff] = block16[(i & 3) | ((i & 0xC) << 1)]; - r->rdsp.rv34_inv_transform_tab[0](s->block[blknum] + blkoff); + ptr[0] = block16[(i & 3) | ((i & 0xC) << 1)]; + if(has_ac) + r->rdsp.rv34_inv_transform_tab[0](ptr); + else + r->rdsp.rv34_inv_transform_dc_tab[0](ptr); } if(r->block_type == RV34_MB_P_MIX16x16) r->cur_vlcs = choose_vlc_set(r->si.quant, r->si.vlc_set, 1); q_dc = rv34_qscale_tab[rv34_chroma_quant[1][s->qscale]]; q_ac = rv34_qscale_tab[rv34_chroma_quant[0][s->qscale]]; for(; i < 24; i++, cbp >>= 1){ + DCTELEM *ptr; if(!(cbp & 1)) continue; blknum = ((i & 4) >> 2) + 4; blkoff = ((i & 1) << 2) + ((i & 2) << 4); - rv34_decode_block(s->block[blknum] + blkoff, gb, r->cur_vlcs, r->chroma_vlc, 1, q_dc, q_ac, q_ac); - r->rdsp.rv34_inv_transform_tab[0](s->block[blknum] + blkoff); + ptr = s->block[blknum] + blkoff; + if (rv34_decode_block(ptr, gb, r->cur_vlcs, r->chroma_vlc, 1, q_dc, q_ac, q_ac)) + r->rdsp.rv34_inv_transform_tab[0](ptr); + else + r->rdsp.rv34_inv_transform_dc_tab[0](ptr); } if (IS_INTRA(s->current_picture_ptr->f.mb_type[mb_pos])) rv34_output_macroblock(r, intra_types, cbp2, r->is16); -- cgit v1.2.3